Business or cruise casual, basically, slacks or Dockers for the men, and a collared shirt of any sort, and slacks, sundresses, skirts for the ladies. Basically casual but nice. I have seen jeans in the dining room, as long as they are clean and presentable and not faded nor torn.
The ship will also have "Formal or not:" nights where you can choose to dress formally or not, many people do, some do not, it is your choice. Whichever way you decide to go, you will not be out of place.
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You are cruising Freestyle. Formal clothes are not required on NCL. You can wear "smart casual" clothes to the specialty dining rooms and the main dining rooms.
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